Observations
-birds seemed to enjoy the wall side more than the sand (birds were on the sand last time)
-crabs were by rocks and the wall
-high tide (tide was at a lower point at previous visit)
-fish were around the plants
-less waves than previous visit
-fish were also out in the open and jumping out of the water
-there had been a decrease of dead carcasses
- lots of fishes are also swimming by the rocks and wall (location of crab)
Proposed Answers
-If crabs were only found on the walls and rocks. Where do they get their food?
The crabs are probably scavengers. They can either eat the dead carcasses that got washed up to shore or they can eat/steal bait from fisherman, who are fishing near by. The crabs eating the dead carcasses could be one of the reasons why I saw a decrease of the dead carcasses. The crabs can also catch the fish in the water but it doesn't seem likely that the crabs eat the fishes because there are no sign of any type of decrease of fish near the rocks.
-Does the tide affect the type of fish that enters the beach?
I believe that the tide does affect the type of fishes that come into the area because when the tide is high, there is more depth in the water for the bigger fishes to swim in. But as the tide slowly lowers, the bigger fish will have a hard time surviving in shallow waters, thus forcing them to leave the beach area and go out into bigger areas of water. The tide can also be a factor to the dead carcasses on the beach. The big fish may have a hard time getting out into bigger and deeper waters, when the tide was lowering, thus trapping them in shallow waters, which they have a hard time breathing in.
-Could the reason of a high bird population mean that birds also inhabit the beach area?
I think that the high bird population does mean that the birds inhabit the beach. They may have a nest there leading to protection of the eggs and babies from other predators such as mongooses. This protection can lead to the birds living a healthy life and undamaged from predators.
-Does the plants act as protection for the birds and fish?
Yes they do act as protection. I think it benefits the fishes more because the plants are placed high along the walls, which makes it hard for predators such as birds to get to it, due to the walls height. The plant also acts as protection for the birds because they can hide their nest in the deeper portion the plants. This makes it harder for predators such as the mongoose to spot the bird nests.
Inferences
-If the tide is at a higher point, then the plants will not act as a source of protection because the distance from the wall/plant will be a shorter distance. Therefore, there will be less amount of fish because the birds will have an easier access to the fish.
-If the tide comes in, bigger prey will approach the area.
-If the tide decreases, than there will be more smaller fishes.
Enviornmental Pressures
Birds can cause natural selection for the plants because if they poop out seeds, and it starts to grow the plants will be able to inhabit the area. Humans can also cause natural selection to the plants because they can either cut it down or grow some more plants with seeds from markets.
-birds seemed to enjoy the wall side more than the sand (birds were on the sand last time)
-crabs were by rocks and the wall
-high tide (tide was at a lower point at previous visit)
-fish were around the plants
-less waves than previous visit
-fish were also out in the open and jumping out of the water
-there had been a decrease of dead carcasses
- lots of fishes are also swimming by the rocks and wall (location of crab)
Proposed Answers
-If crabs were only found on the walls and rocks. Where do they get their food?
The crabs are probably scavengers. They can either eat the dead carcasses that got washed up to shore or they can eat/steal bait from fisherman, who are fishing near by. The crabs eating the dead carcasses could be one of the reasons why I saw a decrease of the dead carcasses. The crabs can also catch the fish in the water but it doesn't seem likely that the crabs eat the fishes because there are no sign of any type of decrease of fish near the rocks.
-Does the tide affect the type of fish that enters the beach?
I believe that the tide does affect the type of fishes that come into the area because when the tide is high, there is more depth in the water for the bigger fishes to swim in. But as the tide slowly lowers, the bigger fish will have a hard time surviving in shallow waters, thus forcing them to leave the beach area and go out into bigger areas of water. The tide can also be a factor to the dead carcasses on the beach. The big fish may have a hard time getting out into bigger and deeper waters, when the tide was lowering, thus trapping them in shallow waters, which they have a hard time breathing in.
-Could the reason of a high bird population mean that birds also inhabit the beach area?
I think that the high bird population does mean that the birds inhabit the beach. They may have a nest there leading to protection of the eggs and babies from other predators such as mongooses. This protection can lead to the birds living a healthy life and undamaged from predators.
-Does the plants act as protection for the birds and fish?
Yes they do act as protection. I think it benefits the fishes more because the plants are placed high along the walls, which makes it hard for predators such as birds to get to it, due to the walls height. The plant also acts as protection for the birds because they can hide their nest in the deeper portion the plants. This makes it harder for predators such as the mongoose to spot the bird nests.
Inferences
-If the tide is at a higher point, then the plants will not act as a source of protection because the distance from the wall/plant will be a shorter distance. Therefore, there will be less amount of fish because the birds will have an easier access to the fish.
-If the tide comes in, bigger prey will approach the area.
-If the tide decreases, than there will be more smaller fishes.
Enviornmental Pressures
Birds can cause natural selection for the plants because if they poop out seeds, and it starts to grow the plants will be able to inhabit the area. Humans can also cause natural selection to the plants because they can either cut it down or grow some more plants with seeds from markets.